Typically a fluid suction container is used in a medical application such as an operating room environment to draw excess fluids away from a surgical field whether such fluids are medical fluids used to irrigate the surgical fluid or the patient's own excess body fluids.
One form of the suction container is a hard plastic canister having a removable cover thereon, with an air-tight seal between the cover and the canister so as to allow a vacuum to be operable within the canister to facilitate the withdrawal of excess fluids from the surgical field.
Because the canister is rigid and must be of sufficient strength to withstand the vacuum forces operative within the canister during its period of use, the cover is a point of weakness for the canister and must be designed to have sufficient strength and rigidity to prevent it from being drawn into the canister under the vacuum forces in use. Moreover, it is desirable that the cover have means therein to dispose of the fluid collected in the canister during its use in the medical procedure involved.
Because use of a rigid canister required the disposal of medical fluids collected therein, and sterilization after each usage, an alternative configuration for a suction container was proposed. In such alternative configuration a flexible canister liner was attached to a cover to be mounted on a rigid canister with such cover still maintaining sealing means with respect to the canister to assure the integrity of the vacuum provided in the rigid canister. In the alternative container configuration employing a hard cover attached to a flexible liner, such vacuum means is first used to draw the flexible container to its full volume before initiating fluid suction. The vacuum then applies suction to draw excess fluids from the surgical field into the flexible liner during the medical procedure involved, and then the cover and attached liner are removed from the rigid canister for disposal. And, such suction container comprising a rigid cover and a flexible liner can be disposed of after a single usage.
However, whether a suction container cover only is mounted on a rigid canister or the suction cover and its attached flexible liner is mounted on the rigid canister, it may be necessary to dispose of medical fluids after the medical procedure is performed through a pour spout in the cover. In both instances, the pour spout must be positively closed during the medical procedure to enable a vacuum condition for suction within the container and then capable of being opened for pouring of collected fluids from the container for disposal. With PVC cover materials it was possible to use a threaded cap and pour spout to secure the cap on the pour spout in fluid-tight and air-tight engagement. However, for many hospitals it is desirable to use something other than PVC materials for disposable containers, and typically such other materials are incapable of providing a threaded fluid-tight, air-tight connection.
In some instances, it is not necessary to reopen a suction container for disposal of fluids held therein, since many hospitals will incinerate waste containers, fluids and all. However, a substantial number of hospitals prefer to dispose of waste fluids and suction containers separately.